I'm currently testing replication of IBM SVC with Cisco 9222i switches. This is using the Global (asynchronous) mirror option. Both Production and DR storage is at the Production site at present
When I throttle the bandwidth with the tcp-max-bandwidth on the "Production" side we start to get I/O latency on the hosts attaching to the SVC. When we throttle bandwidth at the "DR" side we don't notice a problem.
As this is asynchronous replication the hosts shouldn't be getting I/O latency so the only thing I can think is that when I/O is backing up on the 9222i for transmission it is chewing up switch resources which is slowing the servers access to storage.
Does anyone have any ideas?
Any help appreciated.